Re: What\'s the difference between Stinger XT HP & US?
Sean: here's a reprint of an email I received from Charlie Craft, Streamlight's chief engineer. I was asking questions about the 3C bulb specs. He interjected a discussion about the evolving history of the Stinger and the Stinger HP and compared their bulb output to the Scorpion.
It implies that, although the Stinger and Stinger bulbs were originally identical, they are now identical only in wattage, voltage, and amperage. The filament is different, presumably because of differences in the reflector designs.
-----Original Message-----
From: Charlie Craft [mailto:
[email protected]]
Sent: Thursday, April 04, 2002 1:25 PM
Subject: Re: Streamlight 3C
The 3C lamp draws about 785 mA.
The efficiency of the reflector has a much reater effect on CP than the actual power of the lamp.
The Scorpion lamp is only about 20% less ower than the Stinger, but the Stinger has double the CP because of the deeper reflector which intercepts more of the light.
Our new Stinger HP lamp is identical in power to the standard Stinger lamp (the earliest ones were the SAME filament), but delivers 2-1/2 times the CP, solely because of a more efficient reflector.
Remember that lamp power = heat, and heat means more expensive materials.
In addition, the current draw of the lamp must be matched to the current capacity of the batteries, not only to deliver an acceptable run time to the majority of our potential customers, but more importantly to
operate in the "plateau" area of the voltage vs time discharge curve. A flashlight is at it's peak CP at the moment of turn-on with fresh batteries, and goes downhill from there (except for lithium primary cells which actually deliver MORE power after about 10-15 minutes of run time because of internal heating). Using too high a current lamp results in a very steep discharge profile.
Charlie Craft
Chief Engineer